High-resolution deep imaging of live cellular spheroids with light-sheet-based fluorescence microscopy

Two-dimensional cell cultures fail to replicate the complex three-dimensional architecture of real tissues. Real tissues involve intricate interactions between cells and the extracellular matrix across all spatial dimensions. These interactions are absent in two-dimensional models, limiting their usefulness for accurate biological studies. Over recent years, three-dimensional cell cultures have emerged as a more realistic alternative. Differences between two- and three-dimensional cultures are significant at both morphological and molecular levels. Three-dimensional models better mimic tissue-like environments, offering improved in vitro tools. Fluorescence imaging provides insights into cellular processes in three-dimensional settings. However, imaging three-dimensional cultures presents unique challenges. Techniques must allow deep penetration, high speed, and minimal light intensity to avoid phototoxicity.

This review aims to highlight the advantages of three-dimensional cell cultures over two-dimensional models. The focus is on how three-dimensional models better replicate real tissue environments. The study also addresses the specific challenges of imaging three-dimensional cell structures. Fluorescence microscopy is a key tool for observing cellular processes in these models. However, traditional fluorescence techniques may not meet the demands of deep imaging. The review explores how light-sheet-based fluorescence microscopy (LSFM) addresses these challenges. The goal is to establish LSFM as a suitable imaging method for three-dimensional cultures. The review also emphasizes the importance of maintaining cellular viability during imaging. The ultimate aim is to improve the accuracy of in vitro studies using advanced imaging techniques.

The review approach involves a synthesis of recent literature on three-dimensional cell cultures and imaging techniques. Fluorescence microscopy is compared to other imaging modalities in terms of suitability for three-dimensional models. The review evaluates the performance of LSFM in deep imaging applications. Key factors include penetration depth, imaging speed, and excitation light intensity. The review also considers the impact of phototoxicity on cellular viability. LSFM is analyzed for its ability to capture dynamic processes in three-dimensional space. The review compares end-point and long-term imaging outcomes using different techniques. The synthesis emphasizes the advantages of LSFM in maintaining sample integrity while capturing detailed images.

Three-dimensional cell cultures exhibit significant differences from two-dimensional models in morphology and molecular behavior. Fluorescence imaging reveals these differences through detailed visualization of cellular processes. LSFM provides deep penetration into three-dimensional specimens without damaging the cells. The technique allows high-speed imaging, which is essential for capturing dynamic events. LSFM minimizes phototoxicity by using ultra-low excitation light intensity. This feature is crucial for long-term imaging of live cellular spheroids. The review highlights LSFM as the preferred method for three-dimensional imaging. The findings suggest that LSFM is essential for studying cellular dynamics in three-dimensional space.

The review suggests that three-dimensional cell cultures are superior to two-dimensional models in mimicking real tissue environments. LSFM is highlighted as a suitable technique for deep imaging of live cellular spheroids. The review proposes that LSFM offers a favorable combination of penetration depth, speed, and low phototoxicity. These features make LSFM ideal for long-term and dynamic imaging of cellular processes. The synthesis indicates that LSFM is essential for accurate in vitro studies of three-dimensional cultures. The review emphasizes the importance of maintaining cellular viability during imaging. The authors propose that LSFM is currently the technique of choice for three-dimensional cell imaging. The findings support the use of LSFM to bridge the gap between in vitro models and real tissues.